1. Field of the Invention
The field of the invention described herein is ladders. Specifically, the invention is directed to ladders designed for use on inclined roofs. Still more specifically, the invention relates to an extension ladder, a portion of which can be raised over and onto an inclined roof for use thereon.
2. Description of the Prior Art
The requirements of roof and chimney inspection and repairs, painting, and the erection of roof television antennae have created a demand for a ladder which can readily and safely be placed in position and safely used on an inclined roof by home owners and artisans, including skilled carpenters and masons. The ladder described in this specification is of a type which extends up one side of a gabled or a hip roof, over the roof ridge and down the other side, the angular extension of the ladder over the ridge providing great stability and a safe support for a worker when taking roof measurements, repairing an existing roof, repairing chimneys or flashings, carrying materials up and on the roof for further construction, etc.
The prior art reveals previous attempts to devise roof ladders. U.S. Pat. No. 37,470 which issued on Jan. 20, 1863, shows a single hinged ladder section mounted upon the upper portion of one section of an extension ladder. This patent shows that the upper hinged portion of the hinged ladder section may be held in a straight position by means of a rope until the hinged portion is positioned above the eaves of the roof.
U.S. Pat. No. 836,785 which issued on Nov. 27, 1906 shows a fire ladder in which a rigid roof section is hinged to a conventional standing ladder.
U.S. Pat. No. 2,781,158 which issued on Feb. 12, 1967 shows a roof ladder, independent of a conventional building ladder, in which a rigid upper section can be pivoted with respect to a rigid lower section. In use, the rigid upper section extends beyond the ridge of a gabled roof and the rigid lower section rests on the near incline of the roof. In operation, both sections are locked in a linear relationship until the lower section end is placed near the ridge of the gable. A line is then used to allow the upper section to pivot about the end of the lower section until it is in place on the far incline of the gable.
U.S. Pat. No. 900,232 issued on Oct. 6, 1908 shows ladder sections each having a number of rungs connected to one another by hooks. When used as a roof ladder, the patent teaches that it can have one or more sections disposed beyond the ridge.
It is an object of this invention to provide in a single ladder not only an inexpensive roof ladder which provides for safety and stability when in use on a gabled or hip roof, but also an extension ladder of a design which allows a man acting alone to put the ladder in place on the roof.
One advantageous feature of the invention is that it can be used for the dual purpose of a roof ladder and a conventional ladder. It can be used on a gabled or hip roof regardless of the pitch of the roof. It can accommodate roofs of various sizes. Because it is an extension ladder, it is stored and handled easily.